A type of autoclave is currently used in the retread industry. The autoclave typically includes a chamber having an elongated cylindrical shape capable of holding a plurality of tires. The tires are suspended in the chamber to allow heated air to circulate to the outer circumference of the tire and tread. Operated under pressure, heat air is circulated to fully cure a new uncured tread and permanently adhere it to the prepared tire casing. Heated air is accelerated through a fan at the inlet section and is conducted through a circumferential duct, where it is heated by electric wires to a desired cure temperature.
One type of problem with retread autoclaves is that the temperature in the chamber may be uneven, and there may be hot spots and cold spots. The cold spots can result in uneven curing of the tires. An improved autoclave is thus desired, which proves more uniform heating and requires less energy. It is further desired to have an improved autoclave which reduces the cycle heating time.